Power transmitting mechanism



April 1946- L. R. BUCKENDALE ET AL 2,399,291

POWER TRANSMITTING MECHANI SM Filed Dec. 1, 1942 2 Sheets-Sheet 1 Lawrence R Buc/(enoa/e A ril 39, 1946. L. R. BUCKENDALE ET AL 2,399,201

POWER TRANSMITTING MECHANISM Filed Dec. 1, 1942 2 Sheets-Sheet 2 Lon rence A. zfiu ckenoa/e Beyer/y W A eese Patented Apr. 30,1946

POWER TRANSMITTING MECHANISM Lawrence R. Buckendale, Detroit, Mich, and Beverly W. Kecse, Oshkosh, Wia, asaignors to The Timken-Detroit Axle Company, Detroit,

Micln, a corporation of Ohio Application December 1, 1942, Serial No. 467,52; "1 Claims. (01.74-389) This invention relates to power transmitting mechanisms, and more particularly to auxiliary transmissions or transfer cases for transmitting power from a prime mover to two or more drive axles of an automotive vehicle, in which the axles are of the hypoid type and the transfer case is operable to rotate the hypoid pinions in opposite directions, permitting interchangeable front and rear axles to be used, by merely rotating the axles through one hundred and eighty degrees in a vertical plane, although it is not limited to such use.

While transfer cases of this general character have been heretofore proposed, they are open to the disadvantages that they are of complicated design, embodying a multiplicity of shafts rotatable about four or more spaced axes; are bulky and take up valuable space in the vehicle chassis; and also are not readily convertible to conventional bevel gear axle drives, in which the pinion shafts of theaxles are rotated in the same direction. s

We have found that by providing a basic threeshaft transfer case with a split or sectional final drive shaft, and journalling the shaft sections in a support located inside the case, and providing a bevel gear assembly for rotating the final drive shaft sections in opposite directions, a thoroughly practical transfer case of rugged compact construction is secured, which will efficiently transmit power to reversed hypoid axles, and that by providing the transfer case with a third driven shaft, and aligning it with the drive shaft and driving it in the same direction as one of the split shaft sections, it may be employed to transmit power to a third drive axle. Also, by incorporating certain other novel features in the design of the transfer case, it may bereadily changed over to embody a final drive shaft assembly having two axle driving shaft sections rotatable in the same direction, permitting ready conversion to a transfer case for driving conventional bevel gear axles, and yet retaining the basic three-shaft design of transfer case.

It is accordingly the major object of this invention to provide a novel transfer case of compact, rugged design, embodying shafts rotatable aboutthree spaced axes, which will efilciently transmit power in opposite directions to the pinion shafts of hypoid axles, and which may be converted for use with conventional bevel gear axles, in which the shafts are rotatable in the same direction.

A further important object is to provide a transfer case having a drive shaft and a countershaft, with a novel driven shaft assembly disposed to one side of the countershaft and made up of two axially aligned sections, one of which derives power from the countershaft and the other is driven by a bevel gear assembly and transmits power between the driven shaft sections in opposite directions, for reversely rotating motor vehicle drive axle pinion shafts.

Another object is to provide a novel transfer case having a driven shaft assembly made up of a pair of aligned shafts mounted for independent rotation in a housing, with each of their neighboring ends joumalled in a bearing inside the housing and having means for transmitting power from one shaft to the other.

A further object is to provide a novel transfer case having a drive shaft deriving power from the vehicle engine, and which may be used either: (1) to drive the pinion shafts of the front and rear drive axles of a four-by-four vehicle in opposite directions; (2) to drive the pinion shafts of the two rear driving axles of a four-by-six vehicle either in the same or in opposite directions by mounting it respectively ahead of, or between, the two rear driving axles; '(3) to drive the pinion shaft of the front axle of a six-by-six vehicle in one direction and the pinion shafts of the two rear axles in the opposite direction, with one of the rear axledriving shafts aligned with the drive shaft and the other rear axle driving shaft aligned with the front axle driving shaft; and which may also be modified, by a minimum of interchange of parts, to provide a pair of aligned axle driving shafts which are rotatable in' the same direction.

Another object is to provide a novel drive mechanism for dual rear drive axle vehicles embodying a transfer case disposed between the axles and transmitting power in opposite directions to the axle pinion shafts.

Further subordinate objects are to improve and refine certain other features of the transfer cases heretofore proposed; to provide an improveddeclutching mechanism for interrupting the drive to certain of the shafts; to provide improved lubrication means for insuring lubrication of bearirgs and other parts; and to provide novel bearing and support assemblies for journalling a pair of driven shafts for independent rotation in a housing.

Further objects will become apparent as the specification proceeds in conjunction with the annexed drawings, and from the appended claims.

In the drawings: Figure 1 is a longitudinal sectional view through a transfer case embodying the invention, taken substantiallyon the line li of Figure 3, looking in the direction of the arrows;

Figure 2 is a fragmental right-hand end view of the transfer case illustrated in Figure 1. with the housing partially broken away to illustrate the support for the neighboring ends of the driven or output shaft sections;

Figure 3 is a right-hand end view of a transfer case shown in Figure 1 on a reduced scale;

Figure 4 is a fragmental sectional view of the shiftler mechanism for th clutch shown in Figlire Figure 5 is a diagrammatic longitudinal sectional view illustrating the application of the transfer case of the invention to a four-wheel drive vehicle;

Figure 6 is a view similar to Figure 4 but illustrates the invention as being applied'to a sixby-six vehicle drive; and

Figure 7 is a view similar to Figures 5 and 6, but illustrates a novel manner in which the transfer case of the invention may be applied to a six-by-four vehicle drive.

With continued reference to the drawings, in which like reference characters have been employed to designate like parts throughout several view thereof, and referring particularly to Figuges 1, 2 and 3, the transfer case of the invention is mounted in a housing H. rigidly secured to longitudinal vehicle frame members II and I2 by cap screws or the like in well known manner. It will. be noted that this housing i of substantially L-shaped form, having a short upper vertical portion and a lower horizontal portion of substantially the same length and width as said upper portion. Thus, the vertical overall dimension of the housing is reduced to a minimum, as-

suring adequate road clearance in vehicles having a low center of gravity.

The housing i made up of a deep section or casing l3, and a mating shallow. section or cover II, which are rigidly secured together along a transverse plane i5, by cap screw Ii. Journalled in a bearing il in one wall of the housing, and

speed operation or with a spur gear 39 keyed to a countershaft 4|, for low or geared speeduperation. It is to be'understood that any well known suitable shifter mechanism may cooperate with yoke groove 35 of gear 31 to shift it from the neutral position illustrated in Figure having a universal joint flange I! splined thereon The other end of shaft II i provided with a reduced portion 24 which i journalled in a bearing 25 carried in a recess in a gear 2. The latter is provided with an integral shaft portion 21 iournalled in bearings 28 and 28 carried in a sleeve 3| bolted to the housing cover. The outer race of bearing 29 is locked against displacement by means of a ring 20 and a cooperating set screw and lock nut assembly 20a. Splined on the end of shaft 21 and secured-by a nut 32, is a universal joint flange 38 from which power may be transmitted to a drive axle, in a manner to be hereinafter pointed out. A seal ll, carried by sleeve 3i, and cooperating with the hub of flange 33. seals the part against lubricant leaking.

Slidably splinedu on shaft 2i, and having a shifter yoke groove 30, is a spur gear 31, which is selectively meshable either with a series of internal teeth," in gear II, for high or direct 1 into the high speed position or the low speed position, a specific disclosure thereof being omitted to simplify the disclosure.

Shaft 4| is mounted for rotation in bearings 42 and 43 mounted in a closure cap 44, and in cover I4 of the housing respectively, bearing 43 being maintained in place by a bolted closure cap l5. The inner races of bearings 42 and 43, together with the'hub of gear 39 and the hub of a second countershaft gear 61; are clamped between a split ring 48, sprung into a groove in shaft ll, and a plate 49 by means of cap screws 5|. Also keyed to shaft M i a speedometer drive worm 52 meshing with a worm gear 53 for driving the vehicle speedometer in well known manner.

We have found that by providing the transfer case structure just described with the novel split or sectional output shaft assembly that will now be described in detail, it is possible to drive inverted hypoid axles in opposite directions efiiclently with the basic three-shaft case disclosed,

and yet the mechanism takes up substantially no more space than a conventional three-shaft transfer case in which both shaft sections are rotated in thesame directioh. Also, the structure lends itself readily to conversion into atransfer case having aligned concentric output shafts rotatable in the same direction, in which most of the parts of the illustrated transfer case may be used, and which retains its three-shaft character and the same shaft center relationship.

Referring now more particularly to Figures 1 and 2, coun'tershaft gear 41 constantly meshes with a gear 55 keyed to shaft section 56 of a bevel gear 51, so that shaft 56 is constantly rotated in the same direction as shaft 21, and gears and II are preferably the same diameter so that their respective shafts 21 and 56 ar driven at synchronous speeds.

Shaft 56 is Journalled in a bearing 58 carried by housing cover H, and is secured in place by a cap 58 carrying a seal 6i and secured to the housing cover by stud and nut assemblie 62.-

. Splined on the end of shaft 56, and secured by a nut 63, is a universal joint member 64, whose hub cooperate with seal 6i. Member 64 may be. coupled to drive an axle pinion in the manner to be pointed out later.

concentrically disposed with shaft 56, and joumalled in a bearing 66 in housing section I3 which is secured in place by a cap 61 and stud and nut assemblies 68, is a second driven or output shaft H. Splined to shaft H, and secured by a nut 12, is a universal joint member 13, which may be coupled by suitable shafting to a vehicle front drive axle or to the forward axle of a multi rear axle assembly, as will be hereinafter pointed out. A seal 69 carried by cap 61 cooperates with the hub of member 13. Journalled on shaft H, by means of a bushing 14, is a bevel gear 15. which is preferably the same size as bevel gear so a to produce equal and opposite rotation of the output shafts. Shaft II and gear 15 carry matching clutch teeth 11 and I8, respectively, and an internally toothed clutch member 19 is axially slidable upon teeth 11 and may be selectively brought into mesh with teeth I8, for coupling gear 15 to shaft H. Clutch member 19 has a peripheral flange 8i fitting in a shifter yoke 82, and the latter is mounted on a shaft or shifter rail 88 (as seen in Figures 2 and 4) for axial shifting movement in the housing to brin the clutch into and out of engagement with teeth 18 to connect gear 18 to disconnect it from shaft II, as may be desired. A spring loaded detent assembly 88, cooperating with notches in the shifter r il. yl sly holds the parts in either shifted position. Shaft or rail 88 may be shifted by any suitable control device (not shown) operated from the vehicle cab. V

The neighboring ends of shafts II and 88 are supported in novel manner in the housing by a common support and bearing assembly of novel construction, which maintains the shafts in accurate alignment, takes up a minimum of space between the gears on the shaft and enables interchangeable bearing assemblies to be used.' Referring to Figure 2, a vertical support 88 extends transversely-across and is supported at its ends by the opposit wall of housing section I8. Support 88 is provided with stiffening ribs 88, which merge into a central hub portion 88. dispo ed in accurate alignment with bearings 88 and 88, mounted in the housing side walls. Member 88 also supports one end of shifter rail 88, as seen in Figures 2 and 4.

Ri idly secured in hub 88, by means of a set screw 81, and havin a reduced portion 88, and an enlarged portion 88 providing a shoulder seating a ainst one fac of the hub, is a shaft support 8 I.

Shaft 88 is journalled on member 8I by means of a plural ty of race-less anti-friction rollers'82. having a spacer cage or retainer 88. Rollers 82 cooperate directly with reduced portion 88 of su port 8| and with an internal raceway provided in a recess 88 in shaft 88.

Shaft II i provided with a reduced portion 88 which projects into a recess 81 in support M, and is .iournalled therein by a plurality of rollers 88 having a spacer cage 88. Member M is also preferably provided with a central passage I8! to provide free inter-communication of lubricant between the two bearings, and a radial port- I88, into which lubricant adhering to gear 88 is adiapted to be centrifugally thrown during opera on.

From the above it will be evident that by the provision of the aligned. power output shaft II and 88, having driving connection with the front and rear axles, respectively, I am able to employ a single counter-shaft, with a very compact arrangement of the power transmitting mechanism in a housing of minimum dimensions. Also, this aligned relation of said shaft makes it possible to locate the front and rear axle drive gearings on the center line of the vehicle, with a desirably small vertical or horizontal ang'ularity of the propeller shaft connections.

Gears 81 and I8 constantly mesh with a bevel gear I82, having a shaft portion I83 journalled in a pair of anti-friction bearing I88 and I08, carried by a bearing sleeve I88. As seen in Figand is also secured in place by the stud and nut assemblies.

Operationv With the parts in the positions shown in Fi ure 1, the transfer case is in neutral condition and shaft 2| merely idles "in its bearing I1 and 2| and no, power is transmitted to shafts 21, 58

. of the countershaft,

ure 1, the bearings are maintained in adjusted position on shaft I88 by means of a nut I88, and the outer bearing races abut an internal shoulder I88 in the bearing sleeve.

Sleeve I88 is provided with an accurately formed piloting surface I88, snugly fitting an opening in housing section l8, and a flange III which is tightly secured to the housing by a plurality of stud and nut assemblies II2. A clo sure plate II8 fits over the outside of the flange When gear 81 is shifted to the left in Figure *1.

posed in low or geared speed. Under these conditions gear 81, which is smaller than gear 38, drives the latter at reduced speed, and through countershaft gear 41, and gears 28 and 55, drives shafts 21 and 88 at synchronous speeds. With clutch I8 in the disengaged position shown, rotation of shaft 88 as just described, through gears 81 and I82 rotates gear I8 reversely to shaft58. and it merely idles on its shaft. When'it i desired 'to drive shaft II, shift rail 83 is shifted to the right, to engage clutch I8 with teeth I8 of gear 18, whereupon shaft II is rotated at the same speed as shaft 88, but in the opposite directiOn.

When gear 81 is shifted to the right in Figure 1, into mesh with internalteeth 88 of gear 28, the parts are in high or direct drive condition. and gear 81, through teeth 88, drives shaft 21 at the same speed as drive shaft 2|, and, through gears 41 and 88, synchronously drives shaft 88.

Clutch I8 may be shifted when the parts are in the high speed ratio for either causing shafts 88 and II to be driven in opposite directions or for causing shaft 58 alone to be driven, at the same speed as the drive shaft 2 I.

Power may accordingly betransmitted at either the high-or the low speed ratio to shaft 58, and clutch 18' is selectively shifted to drive one or both output shaft sections.

By making idler pinion I82 of small diameter than gears 8Iand I5 the latter may be brought sufficiently close together to permit compact installation of the gears in a housing of substantially conventional size, but it is to be understood that the invention is not limited to any specific gear ratios. Also, by mounting gears 51 and I8 on shafts 88 and II, respectively, in the locations disclosed, so as to be disposed either side of, and in nesting relationship with, gear 38 (Figures 1 and 2) an extremely compact structure is realized.

Lubrication Lubrication of all the parts is provided by maintaining lubricant at a predetermined level in the housing and providing lubricant pockets and ducts that will now be described to conduct lubricant to. all of the bearings. Referring to re 1, spur gears 88, gears 51, I82 and 15 dip directly into the body of lubricant in the housing and are therefore adequately lubricated at all times. Gears 38 and in turn adequately lubricate the teeth 0i gears 81 and 28, and adequat lubricant finds it way into bearing 25 by splash during low speed operation.-

A pocket M8 on the side wall of housing section I8 traps lubricant splashed against the housing and finds its way through a duct H8 in the housing wall and a mating duct H1 in cap 22 to bearing IT. A similar pocket M8 in cover section I8 transmits lubricant through duct I I8 and I2I to bearings 28 and '28.

Countershaft bearing 82 is lubricated by a pocket I22 in the wall of housing I8 which com- 8I, 58 and I8 and bevel municates with a duct m m the housing side wall and a duct I24 in cap 4!. Hearing 43 is lubricated by a similar pocket I25 communicating through a duct I26 in cover section II and a duct I21 in cap 45 with the bearing.

Bearing 58 for shaft section 58 is lubricated by a pocket I28 and communicating ducts I29 in cover section I2, and I3I in cap 59. A similar pocket and duct arrangement may be provided for bearing 66, but since this bearing only operates under load and when clutch I9 is engaged, the lubricant splashed from the gears is usually sufficient.

In the foregoing discussion of the various pockets it i to be understood that they are disposed substantially directly over their respective bearings, but that they have been shown out of their proper planes to simplify the disclosure. Roller bearings 92 and 88 are lubricated by splash from gear 39, the lubricant entering passage I00, which faces the gear, and freely passing through central bore IOI to both bearing assemblies.

convertibility If it is desired to convert the transfer case of the invention-to one-in which the two aligned output shafts rotate in the same direction. the construction of the parts permits this to be readily carried out without changing the basic threeshaft design. Shaft section 66, II and Ill and their associated gears are removed and replaced by two plain shaft sections, one of which p jects to the left through, and is journalled in, support 9i, gear 55 being mounted upon one of the shaft sectionsrand'clutch I9 being utilized to couple one shaft section to the projecting portion of the other when it is desired to drive both shaft sections synchronously.

Applications to vehicle drives Referring now to Figure 5, we have diagrammatically illustrated a vehicle having front wheels I driven by a hypoid axle I. and rear wheels I37 driven by'a hypoid axle I38, it being observed that front and rear axles are rotated substantially 180 in a vertical plane so as to dispose the front propeller shaft M2 above the axis of the axle shafts, and the rear propeller shaft t I below the axle shaft plane, requiring opposite direction of propeller shaft rotation. Power is transmitted to input shaft universal coupling I 8 by mean of a drive shaft I40. As seen in Figure 5, a propeller shaft IJI i connected to universal joint connection 66 of shaft 56, while -propeller shaft I42 is connected to universal joint connection "of shaft II. In this application of the invention universal Joint flang 33 of shaft 21 is not untilizedfor transmitting power and if desired may be removed and theshaft capped over.

In Figure 6 there is illustrated a six-by-six hypoid axle drive in which all of the driven shafts of the transfer case are utilized to transmit power. Front drive axle I38 is connected to universal joint coupling II by propeller shaft I39 as in Figure 4. while drive axle I38 is connected to output coupling 64 by propeller shaft I". The vehicle is provided with an additional drive axle I, having wheel I 45, which is driven from universal joint coupling 33 of shaft 27 through a pair of propeller shaft I" and I and a short shaft section H9 iournalled in a support IBI carried by the vehicle frame.

The invention may be applied to a six-by-four vehicle by merely omitting the front propeller or, if desired. the novel alternative drive shown a in Figure 'I may be utilized. Referring to Figure 7, front wheels I35 are carried by a dead axle I52, and rear drive axle I38 of Figure 6 has been inverted so as torequire reverse rotation. The transfer case i mounted between the drive axles on the vehicle frame in any suitable manner and joint couplings 54 and 13 of shafts 56 and II are coupled to axles I and I38 by short propeller shafts ISG and I55 respectively. Here again shaft 21 is not utilized for transmitting power and may be capped over if desired.

From the foregoing detailed disclosure of the invention it i apparent that we have provided a novel transfer case and vehicle drive mechanism particularly adapted for driving hypoid drive axles and embodying aligned output shaft sections rotatable in opposite directions, and a third output shaft for transmitting power to a third drive axle, which is of rugged and compact design and which will efliciently transmit'power to two or more axles, and embodies a novel split output shaft assembly having means for jour- ---nalling the two shaft sections in closely neighboring relationship for independent rotation inone set of driving wheels to save tire wear, the

invention is also applicable to transfer cases in which the two shaft sections are constantly driven.

While we have shown the invention as being applied to axles requiring a one-to-one driving relaticnship'of the propeller shafts, it is to be understood that it is also applicable to vehicle drives in which one axle has a different ratio than the other, by making gears I7 and 15 of f different diameters and employing either an:

obliquely mounted idler gear, or two idler gears. rigidly connected together and each meshing with one of the different diameter output shaft gears, and it is to be understood that the appended claims embrace the invention when embodied in these forms.

The invention may be embodied in other speciflc form without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by th foregoing description, and all changes which come within the meaning and range or equivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States Letters Patent is:

1. In a power transmitting mechanism, a housmg; a drive shaft mounted for rotation in said housing; a pair of axially aligned driven shafts mounted for rotation in said housing about an axis spaced from said drive shaft; 9. pair of spaced bevel gears mounted on the neighboring ends of said driven shafts and meshing with a third bevel gear mounted for rotation in said housing;

- and means for transmitting power from said aseaaoi prising a spur sear mounted-for rotation about an axi parallel to said driven shafts and projecting into the space between said bevel gears carried by said driven shafts.

2. In a vehicle having a pair of driving axles; a transfer case for transmitting power from a prime mover to said axles, comprising a housing adapted to be mounted in the vehicle in cooperative relationship to said axles; a drive shaft journalled in said housing; three driven shafts journalled in said housing for rotation about substantially parallel axes; means for transmitting power from said drive shaft to said driven shafts, comprising a countershaft carrying a gear, scars on twoof said driven'shafts meshing with the gear on said countershaft; means for transmitting power from one of said two driven shafts to the third of said driven shafts and operable to rotate the latter in the opposite direction to the other of said driven shafts; and means for transmitting power from two of said driven shafts to said drive axles.

3. The vehicle drive mechanism defined in claim 2, wherein said vehicle is provided with a third drive axle and is connected to said third driven shaft.

4. In a power transfer mechanism for a plurality of vehicle drive axles, power input and output shafts axially aligned with each other, an additional pair of output shafts axially aligned with each other, each of said output shafts being adapted for driving connection with a different vehicle axle, power transmission gearing between said first named output shaftv and one of the latter output shafts, and manually controllable means individual to the respective pairs of aligned shafts for establishing a power transmitting onnection between the shafts in each pair.

5. The power transfer mechanism defined in claim 4, and a housing therefor having angularly related portions of substantially equal length.

6. In a power transmitting mechanism for front and rear hypoid gear driven axles in which the hypoid pinion shafts are driven in relatively opposite directions; power dividing means comprising a pair of coaxially aligned power output shafts for drive transmitting connection with the respective axle pinion shafts, a power driven shaft, a single counter-shaft between said latter shaft and the power output shafts, constantly meshed gears fixed to the driven haft, countershaft and one of said output hafts, and manually controllable means operable to establish a driving connection between the opposed endsof said aligned shafts and to drive the other output shaft in a reverse direction 'to said first named output shaft.

7. The power transmitting mechanism defined in claim 6, and a substantially L-shaped housing therefor having a lower horizontally disposed portion in which said aligned output shafts are mounted below a horizontal plane intersecting the axis of the counter-shaft.

LAWRENCE R. B UCIENDALE. BEVERLY W. KEESE. 

